Hot-blast stove.



m MAGS.

Gr.v H. SMITH, DEGD. N. 1:. SMITH. .aDMINIMRMRIXv HOT BLAST STOVE.

IlllllllllHlllllilllllll llllllllllllllll APPLICATION P ILBI) JULY 10, 1913.

Patented Oct. 20, 1914.

5 SHEETS-SHEET 1.

G. H. SMITH, DED. I N. n. SMITH, nnmsn'rmx.

HOT BLAST STOVE.

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W EN E G. H.KSMITH, DBCD. N.' E. .SMITIL ADMINISTBATRIX HOT BLAST STOVE.

` APPLICATION FILED JULY 1S), 1913.

Patented o@t.2o,1914.

FIGJ

wgysas M@ MV G- H. SMITH, DECD.v N. n. smTHfADMINIsTRATRIx HOT BLAST STOVE.

APPLICATION FILED JULY 10,1913.

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5 SEEET-SHEET 4.

FBGKH G. H. SMITH, DECD. N, E. SMITH, ADMINISTRATRIX HOT BLAST sTovE. A APPLICATION FILED, JULY 10, 1913.

l N V E NTO R GMIyeHWWoM,

WITNESSES y Patented 0ctf1914- y ried from the bottom of the stove.

entran sfrafriis PATENT lormoni.

GEORGE H. SMITH, DECEA-SED, LATE OE ,ASPINWALL PENNSYLVANIA, BY NELLIE E. SMITH, ADMINISTRATRIX, OF ASPINW'ALL, PENNSYLVANIA. i

Hor-BLAST strovn.

T0 all whom it may concern ceased, late a citizen of the United States residing at Aspinwall, in the county of Alle glieny and State of Pennsylvania, did 1nvent certain neiv and useful Improvements in Hot-Blast Stoves, of which the following is a specification.

The invention has relation to the construction of regenerative hot-blast stoves einployed in heating the air-blast used in blastfurnaces and more particularly to the con- .iti-action and arrangement of the refractory lining and checker-Work -of such hot-blast stoves. In such hot-blast sto-ves the refractory material forming the checkervvork and lining is alternately heated and cooled and after being gradually heated to a high teinperature becomes slowly cooled to between 800 and 1200 degrees Fahrenheit by the action of the colt-blast passed through the steve, the cold-blast absorbing heat and becoming heated to between 800 and 1200 degrees Fahrenheit from the highly heated checl'rer-Work and lining in .passing through the stove and after becoming heated to the desired high temperature the heated air or hot-blast is led tln'ough the hot-blast main into the blast-furnace- .Vith s uch hot-blast stoves the alternate expansion and contraction of the refractory lining and the checkerwora caused by the alternate heating` and cooling thereof together with the enormous cf-flight of the refractory materials forming the lining and checkerwork makes it difficult if "iot impossible to prevent or avoid crushing and crumbling thereof. The Weight of the refractory checkerwork and crushing .strength of the cheekerwork has been a factor limiting the economical height to which thestoves can lre huilt, as the lining and checkers have always been supported or carn .As the diameter or cross section ofthe stove compared with the height is relatively small and as all of the checkerwork must be removed to enablel the bottom series o'f courses of the cheokerwork to beremoved.y the time required in relining or repairing the checkerwork causes a long delay and serions inurruptionin the operation of the stovesy Specification of Letters Patent.

Application filed 'July 10, 1913.

Patented Oct. 20, 1'914.

Serial No. 778,393.

when such relining or repairing operations become necessary.

@ne obJcct of the invention 1s to provide a hot-blast stove of improved constructioir having novel means whereby the capacity and efficiency of the stove are materially increased.

Another object of the invention is to provide a stove construction having novel means whereby the heating surface of the stove is greatly increased and the flowof the air-blast through the stove is equalized and more uniformly distributed.

A further object of the invention is'to provide a stove having a refractory lining and checkerwork of novel construction and having improved means whereby the check* crvrork is supported in the stove and the weight of the refractory materials forming the checkerwork is distributed Within the stove shell.

A, still further object of'this invention is to provide ahot'blast store. having improved means Whereby the necessity of entirely removing the lining and checkerwork from the stove in renewing and repairing the. lining or checkerwork is avoided and the time required to reline the stoves is greatly lessened and the cost of maintaining the ,stoves in operative condition is materially reduced.

Still further obj ects of theginvention will become apparent ,as the invorrtionisv hereinafter more fully descriliiedand claimed.

Referring to the accompanying drawings forming` Part of this specification," Figure l is a, vertical section of a two-pass hot-blast stove having a central combustion chamber and having a refractory lining and checker-l work therein constructed and arranged in accordance .vit-h the invention. Fig. 2 is a sectional plan showing the construction and arrangement of the checkers, the checkersupporting girder tiles and the radial tile supporting arches used .in this type of stove in accordance with and forming part of the invention, the upper half of the section being takenon the-irregular line lll-ll, and the lower half ofthe section being taken on the line lla-lla of Fig. l. Fig.- 3 is a` sectional plan taken on the line III-III of of Fig. 6. Fig. 6 is asectional plan, the

upper half of the figure showing the arrangement of they checkers being1 taken on the line VI-VI and the lower alf showing the girder tiles on the line Vla- VIa of Fig. 4. Fig. 7 is a similarsectional plan taken Qn the line VIL-VH or line V113-,-

.VIIl of Fig. 4 showing the arrangement of the girder tilesu-pporting arches. Fig. 8 is a sectional plan taken on the line VIII- VIII of Fig. 5. Fig. 9 is a sectional elevation showing in detail the manner of supporting the girder tiles upon the stove shell lining. Fig. 10 is a sectional elevation showing a three-pass stove as constructed and arranged in accordance with the invention, the section being taken on the line X- -X of Fig. 16. Fig. 11 is a sectional elevation of the same on the line XI-XI of Fig. 16. i Fig. 12 is a sectional plan taken on the line XII-XII of Fig. 11. -Figs. 13, 14, 15 are similar sectional plans taken respectively on the'llines XIII-XIII, XIV--XIV and XV-XV of Fig. 11. Fig. 16 is a sectional plan taken on the irregular line XVI- XVI of Fig. 11.

In the drawings, referring to Figs. 1, 2 and 3, the numeral 2 designatesl the usual metal hot-blast stove shell having a metal' bottom 3 and metal dome-shaped top 4. The stove is of very considerable height compared to its diameter, and has -a much greater ratio of height to diameter than as been the usual practice heretofore in constructing'hot-blast stoves, such construction being made practicable by carrying'or supporting the upper portion 5 of the checkerwork independently of the lower portion 6 thereof. The stove is provided on its top with a cleaning opening 7 and at the bottom of the stove is equipped with the usual cleaning openings 8, 8, hot-blast loutlet opening 9, gas inlet opening 1 0 and air inlet openings opening 11a. The stove has a cylindrical wall 12 forming a central combustion cham- 'ber 13 which extends from the bottom to the hemispherical open space 14 at the top of the stove, and is also provided with a refractory lining 15 within the metal shell'2, which is arranged to support the domeshaped lining 16 for the top 4. The wall 12 forming the combustion chamber 13 and the surrounding wall 15 forman annular space kof the stove and the handling of'the refrac- 11, and air outlet or relief therebetween, on which the checkerworkis erected, and lasrshown in Figs. 1, 2 and 3, this checkerwork is formed of hollow rnefractory blocks 17 which are trapezoidal .1n cross section. Owing to the very material increase in the height of the stove (from twenty-five to fifty per cent. or more) the total weight of the checkerwork is greatly increased so that if carried or supported in the usual manner the load on the lower horizontal rows of checkers would with the ordinary construction approach or equal the crushing strength of the checkers. In order to more uniformly distribute the weight and thereby lessen and prevent deterioration caused by expansion and contraction ofthe checkerwork, as is constantly occurring in the-operation of thest-ove, in this improved stove construction the upper half 5 of the checkerwork is carried upon girder tiles 18 which in turn are supported-upon arches 19. The arches. 19 spring from and are supported by the side wall 15 and the Wall 12 forming the central combustion chamber 13. The hollow blocks 17 forming the checkerwork in the bottom half 6 of the stove are supported ony similarly constructed and arranged girder tiles 18 which are carred by arches 19 these arches also in this case springing from the bottom of the lining 15 and the wall 12 for the combustion chaml ber 13, as has been described. In this way the greatest load put upon the checkers is lessened instead of increased and a hollow chamber 20 is rovided at an intermediate point in the height of the stovewhich connects with the vertical passages in the u)- per and lower portions 5 and 6 of the checlierwork, this chamber acting to equalize the How of air and also of the products of combustion through the stove checkerwork. A platform or gallery 21 is provided around the top of the stove and also at an intermediate point in its height to facilitate cleaning tories in lining and repairing the stoves. By reference to Fig. 2 it will be seen that the series of arches 19 are arranged radially around the vertical center of the stove and that the girder tiles-18 resting upon the arches 19 arearranged in a series of concentric rows about the vertical center of the stove. Short tiles 22 are placed between the rows of tiles 18 -to serve as' separators or spreaders which prevent lateral displacement of the tiles 18 in the expansive movement thereof. f

In the stove construction shown by Figs. 4 to 9 the metal shell 2 of the stove vis provided .with a metal bottom 3 shaped metal top 4 in the same manner as has been described in connection with the stove of Figs. 1, 2 and 3, and in this construction at the top and at an intermediate point in its -height the stove is pro- 12 and dome- 12 vvided. with a gallery -or platform- 21. In

additionto the cleaning opening 7 there-is acleaningope'ning 28 for the combustion chamber .7, which `in ,this construction is located on ,one side of the vertical center of the stove, instead of being centrally positioned, as in the stove of Figs. 1, 2 and 3.

' Y The combustion chamber 24 in this construction formed by thek wall which lis curved on one face and which extends aeross the stove to separate the combustionchalf1- ber24 from the checkerwork chamber, (see opening 32 and gas inlet 33.

Figs. 6, 7 and 8l and the stove, adjacent to its-lower end and within the chamber for the checkerWo-rk, is provided Witlrcleaning openings 26, 26, an outlet opening 27 to the' chimney, and a cold-blast inlet 28. The bottom-of the combustion chamberv 24 is provided with a gas inlet opening 29, hot-'blast outlet30, an air relief opening 3l, cleaning As in the preceding figures the checkerwork extends from the bottom to the top of the stove and at an intermediate point inthe height of the stove the upper portion 5 of the checke-rworkpis supported on -girder tiles 34 which i'n turn are carried by a series of parallel arches 35, these arches being lsupported on the stove lining 36 and extending across the stove .in lines parallel with a horizontal line through the vertical center of the stove, as is clearly shown in Figs. 4 and 5. The stove has the chamber 20 connecting upper and lower por- 1 tions 5 and 6 of the lcheckerwork and the lining 36 is racked out to form shelves 37.011 which theends of the upper seresof arches 35'rest. The bottom portion 6 of the checkyerwork 33 is carried uponvgirder tiles 34 and parallel arches 35 in the same manner as the upper portion 5, and tiles 38' and 39 vforming spreader-s are positioned between the parallel arches and the `giri'ier tiles 34' to prevent sidewise displacement thereof during the expansion and contraction which is constantly' occurring in the checkerwork when the stove is in use. A series of cleaning openings 4() is provided at an intermediate point in the height of the stove to afford entrance to the open space 20 on the interior of the stoves at a point adjacent to the arches 35 carrying the upper portion 5 of the checkerwork.

In the construction of Figs. 4 to 9. hollowy and with a cold-blast inlet 62.

which a three-pass stove is illustrated,

the` metal shell 2 of the stove is provided with a chimney or stack ,43 on its top instead of having an outlet on its bottom leading to the'chimney as in the preceding figures. lThe stove is provided with a refractory lining 44 and in the lower portion of the stove wlth a cylindrical wall 45 forming a vertical combustion chamber 46 which' extends from the bbttom to an intermedia-te point in the height of .the stove. Within the ace between the shell lining 44 and cylin rical wall 45 are the partition walls 47 which are tied into the lining 44 and wall 45 so as to form eight separate lengthwise vertical passages 48, 49, (see Fig. 14).

`Abovethe topz of the vertical combustion chambenfwhich -terminates at about the middle ofth height of the stove, is an open space .formed by the lseries of four channels 50 which connects the vertical combustion chamber 46 with the checkerworli below the transverse partit-ion walls or arches 51 separating the lower portion of the stove into the four downward-passages 48 (see Fig. 14). The bottom of these downward passages 48 are connected by the.

transverse passages 52 with the series of four upward passages 49 (see Fig. 10)

whichv open into the open space 53 above the arches 51 forming the top of the channels 50connecting the downward passages 48 and combustion chamber 46. A series of parallel sidewise separated arches :34a-re supported upon the stove lining'44 'above the roof formed by the arches 51, and girder tiles 55 are supported upon the arches 54' in the same manner as in Figs. lto 9.

Above'the girder tiles 55 the stove is' provided with checkerwork 56, this checkerwork being formed of hexagonal refractory blocks having a central opening therethrough similar to those shown'in Figs. 4 and 6. -Tlie stove is provided with cleaning'door inlets 57, which also serve as air inlets, a gas inlet 5S, an air relief outlet 59 and with a hot blast outlet 60 at the bottom thereof, and the chimney43 for the stove is provided with a chimney valve 6l 'The chinuiey valve and cold-blast inlet being of known construction are not 'further described.

l Cleaning .door outlets 63.are provided on the top of the stove and also above and below the arches forming the top of the connecting channels 50 at the top of the vertical combustion chamber 46, and galleries or platforms 64 are provided at suitable elevations on the outside of the stove for `use in lining and cleaning the stoves and the outlet openings on the stove are provided with the usual equipmentof doors or covers.

The cleaning openings are allprovided with removable closing doors and suitable air and gas valves and hot-blast and chimnev valves are employed to sh'ut the openings to orfound necessary. Such devices being old I e and well known and not forming-part o bottom of the stove through .the air inlet of through the serial-i of openings in theA hollow checkerwork, passing lout of are then sprung the. chimney or stack. y

lining become heated openings',

heate stove is onair thisI invention are notfurther described.

' The invention 1s not only adapted for use vin the construction of new stoves, but is equally applicable for use in remodeling ex- .isting stoves.

In .applying being raised and securedin place von the top- .of the newdportion of the vstove shell 2. The

arches *19, epending 'upon the type of stove,

fter the girder tiles18 are buil-t. stove yand work 5 is put into place.

- In the operation ofthe improved stovel 1, 2 and 3,- when the stove shown by Figs. 1s being .heated Aor 'on'` gas the gas enters The mixture ofgas and Aalr opening 10.y

open Space 14 at the top vof the stove and then pass downwardly to the bottom 'therethe stove through .the stack outletJ 23 leading to After the checkerwork and refractory to the desired temperaturethe gas supply is shut off and the lgas `inlet and air inlet chimney valve and other openings into the interior of the `stove are then tightly closed. The cold-blast valve on the stove isthen opened' and the cold-blast or air, which is under considerable ressure, is admitted at the "bottom of yt ye 'stove through the cold-blast valve Minto and through'the inlet 23 and, rising upwardly throu h vthe seriesof passages the highly d checkerwork, passes into the open space 14 at the top of the stove and then passes downwardly through the `combustion chamber 13. The; cold-blast in its passage throu h the checkerwork and combustion chamber 13 absorbs heattherefrom, and, upon reachingthe bottom of thel combustion chamber lfof thek stove, 4passes -out ofthe stove l throughfthe hot-blast outlet 9 into a hot-blast main l'leading to the blast-furnace, the hotblast valve beingv opened lwhen the In the operation of the vstove shown in Figs. 4 to 9 when the stove is beingheated on on gas the gas enters through the gas inlet or burner and mixes with the air entering through the air inlet in the combustion chamber 24 in which it burns. The burned whichl they are applied as required the invention to existing` stoves the 'height of the stove is increase to the desired extent, lthe top 4 of the stove from the `|side walls "atan" intermediatey point in theheight of the re-.Sl

through youtlet-3() into gases or. products of combustion rise upwardly through the combustion chamber 24 into the open space 14 at the t'op'of the stove andv then pass downwardly through The cold-blast valve'being opened to adnit the cold-blast throigh the'inlet 2 8 into the bottom part ofthe stove, thecold-blast-rlses upward y j through the checkerwork and lpasses'intogthe'open'space V14 at'the top of thev stove 'and `then .travels downwardly l the combustionch-amber 24, becoming heated inpassing through the stove and passing out through the now open hot-blast the hot-blast main leading to the blast-furnace.'l After the cold-blast passv thestove has cooled the checkerwork to the point where' it is desirable to yagain heat the stove, the cold-blast and'hotblast valves' are closed to preventffurther V passage ofair therethrough; 4 The'air reliefthen -opene'dfto'reduce the air- -confned Iwithin the stove to -1 atmospheric valve e1 is pressure,'the compressed air within the stove being allowed to escape'through the air relief valve into the-atmosphere. Gas is then again caused to burn in the stovel as has been described, and the above described 0peratio'ns are again repeated in heating the checkerwork preparatory to again heating the stove of Figs. 4 to 9 andlater heating the cold-blast.

In the operation of the improved threepass stove shown in Figs. 10 to 16, when the stove is being heated or on gas the chimney valve 61, is open and the cold blast valve on thecold blast inlet 62 -at ,the top.

of the stove and hot blast valve on the vhot blast outlet 59 'at the' base of the stove are closed. The air inlet openings `57 and gas inlet openings 58 are opened to admit gas and air to the central combustion chamber 46; 'The mixture' of gas and air burns in the combustion chamber and after rising to the channels 50 at the top thereof pass downwardly through the vertical passages 48 in the checkerwork to the bottom ofthe stove and then pass through the thensversev o-penings 52 into the passages 49 in the checkerwork. The burned gases then rise in the passages 49 andemerge into the open space 53'below the upper section of the checkerwork and rising through the openings in the checkerwork 56 pass intoand out of the chimney 43 on top'of the stove. After the checkerwork becomes heated to the desired extent the gas'is shut off and the gas inlet 58 and air inlets are closed. The chimney Avalve 61 is then closed and the cold-blast valve on the cold-blast inlet'62 and hot-blast valve on the hot-blast outlet areopened. The cold-blast entering the top of the stove then passes downwardly through the checkerwort 56 in the upper section of the stove into the open space 53 and then passes downwardly through the vertical passages 49A in the lower section of the checkerwork into the transverse passages 52 and then upwardly through the passages 48 into theo en space 5 at the tcp of the lcombustion lchamber. The i air then passes downwardly through the combustion chamber 46 and through the hot-blastoutlet 60 into the hotblast main leading to the furnace bustlepipe. After `the passage of cold-blast through' the steve has cooled the checker work so as to require that it be again heated, the-ccld-blast valve and the hot-blast valve are again closed and the air relief outlet 59 is opened to release the air in the stove and reduce the pressure therein, this'air being allowed to escape into the atmosphere. When the interior of the stove is reduced to atmospheric pressure the gas is' again turned on after the chimney valve has been again openedand the above described operations are then again repeated.

@n account of the very great height of the impro-ved stove a given volume of air is brought into contact with a greater amount of heating surface or heated refractory inaterial during its passage through the stove so that the time interval in which the air is maintained in contact with the highly heated surface of the checke'rwork is practically doubled without material decrease in the pressure and velocity of thel hot-blast passing through the stove, in this way greatly increasing the capacity and eliiciency of the stove.

The advantages of the invention will be apparent to those skilled in the art. The capacity and efficiency of the hot-blast stoves is very materially increased at a relatively small increase in cost. Another advantage of the invention arises from the construction whereby the separate top and bottom portions of the checkerwork are independently supported so that in case the bottom portion should require renewal or repairs, such portie-nenn be removed and replaced without disturbing the upper separately supported portion of the checkerworlr.

Modiiications in. the construction and arrangement of the parts may be. made without departing from the invention; The invention ,may be applied to two and to three pass stoves of other types than the two-pass and three-pass stoves shown, and other changes may be made within the scope of the appended claims.

Claims l. A hot-blast stove comprising a metal l shell, a refractory lining in said shell, a refractory checkerwork within the lining, said checkerworl being formed in horizontally separate and independently supported sections, and a vertical combustion chamber in the sto-ve extending from the bottom to the top of said checkerwork and communieating therewith at the top of the stove.

2. 'A hot-blast stove comprising a metal shell, a refractory lining in said shell, a refractory checkerwork within the lining, said checkerwork being formed in atleast two horizontally separate and independently supported sections, and a vertical combustion chamber in the stove extending from the bott-om to the top of said cheekerwork and communicating therewith at the top of the stove.

3. A hot-blast stove comprising a metal shell, a refractory'lining in said shell, a refractory checkerwork within the lining, said checkerwork being formed in horizontally separate and independently supported scc tions, a verticgl combustion chamber in the stove extending from the bottom to the top of said checlzerwork and communicating therewith at the top of the stove, and a plurality of separate and independent arches supporting each section of the cli-cckerwork. y 4. A hot-blast stove comprising a metal shell, a refractory lining in said shell and checkerwork formed of refractory blocks within the lining, said checkerwork being formed in at least two horizontally separate and independently supportedrsections, a vertical combustion chamber in the stove extending from the bottom to the top of said checkerwork and communicating therewith at the top of the stove, and a plurality of separate and independent'arches supporting each section ofthe checkerwork.

5. A hot-blast stove comprising a metal shell, a refractory lining in said shell and checkerwork formed of refractory blocks within the lining, said checkerwork being formed in horizontally separate and independently supported sections, a vertical coinbustion chamber in the stove extending' from the bottom to the top of said checkerwork and communicating therewith at the'top of I the stove7 a'series'of rows of gird er tiles supporting each section of said checkerwork, and a plurality of separate and independent arches supporting the tiles carrying each section of the checkerwork.

' G. A hotblast stove comprising a metal shell, -a refractory lining in said shell and checkerwork formed of refractory blocks within the lining, said clieclrerworlr being formed in at least two horizontally separate and independently supported sections, a ver tical combustion chamber in the stove eX- tending from the bottom to the top of said checkerwork and communicating therewith shell, a refractory lining 1n said shell, said at the to of the stone,v a series of rows of'l .7'. A hot-blast'stovev comprising a metal checkerwork being formed in horizontally separate 'and independentl -supported sections,and a vertical com ustion chamber in the stove extenng'u'pwardly from 'theI bottom of the' stove.

In testimony whereof, have'herenntoiset my hand.y A v Y NELLIE E. SMITH, AZfrn,z'm'.srtrato,rV .of the estate of George H.

Smith. Y Witnesses:

L.- E. RIDDA" L. P. CAMPBLL.

Copies of this patent may be obtained for ve cents eeen-by addressing the "Commissioner-of Patents. Washington, D. C. y 

